<!DOCTYPE html>
<html>

<head>
    <meta charset="utf-8">
    <title>testD3-27-textforce.html</title>
    <script type="text/javascript" src="./js/d3.v3.min.js"></script>
    <style type="text/css">
    </style>
</head>

<body>
    <script type="text/javascript">
        // https://blog.csdn.net/tianxuzhang/article/details/14223855
        //(1)链接数组
        var links = [
            { source: "Microsoft", target: "Amazon", type: "licensing", weight: 1, color: 1 },
            { source: "Microsoft", target: "HTC", type: "licensing", weight: 3, color: 4 },
            { source: "Samsung", target: "Apple", type: "suit", weight: 4, color: 6 },
            { source: "Motorola", target: "Apple", type: "suit", weight: 6, color: 65 },
            { source: "Nokia", target: "Apple", type: "resolved", weight: 3, color: 76 },
            { source: "HTC", target: "Apple", type: "suit", weight: 8, color: 879 },
            { source: "Kodak", target: "Apple", type: "suit", weight: 7, color: 989 },
            { source: "Microsoft", target: "Barnes & Noble", type: "suit", weight: 9, color: 643 },
            { source: "Microsoft", target: "Foxconn", type: "suit", weight: 1, color: 54 },
            { source: "Oracle", target: "Google", type: "suit", weight: 3, color: 54 },
            { source: "Apple", target: "HTC", type: "suit", weight: 4, color: 45 },
            { source: "Microsoft", target: "Inventec", type: "suit", weight: 0, color: 43 },
            { source: "Samsung", target: "Kodak", type: "resolved", weight: 8, color: 243 },
            { source: "LG", target: "Kodak", type: "resolved", weight: 1, color: 43 },
            { source: "RIM", target: "Kodak", type: "suit", weight: 5, color: 13 },
            { source: "Sony", target: "LG", type: "suit", weight: 3, color: 351 },
            { source: "Kodak", target: "LG", type: "resolved", weight: 4, color: 1 },
            { source: "Apple", target: "Nokia", type: "resolved", weight: 1, color: 1 },
            { source: "Qualcomm", target: "Nokia", type: "resolved", weight: 3, color: 4 },
            { source: "Apple", target: "Motorola", type: "suit", weight: 4, color: 6 },
            { source: "Microsoft", target: "Motorola", type: "suit", weight: 6, color: 65 },
            { source: "Motorola", target: "Microsoft", type: "suit", weight: 3, color: 76 },
            { source: "Huawei", target: "ZTE", type: "suit", weight: 8, color: 879 },
            { source: "Ericsson", target: "ZTE", type: "suit", weight: 7, color: 989 },
            { source: "Kodak", target: "Samsung", type: "resolved", weight: 9, color: 643 },
            { source: "Apple", target: "Samsung", type: "suit", weight: 1, color: 54 },
            { source: "Kodak", target: "RIM", type: "suit", weight: 3, color: 54 },
            { source: "Nokia", target: "Qualcomm", type: "suit", weight: 4, color: 45 }
        ];

        var nodes = {};

        //(2)从链接中分离出不同的节点      
        //一个小问题：节点的weight属性怎么产生的？               
        links.forEach(function (link) {  //思路就是：在连接中遍历链接，节点数组有了这个链接的源节点就把链接指向这个节点。没有的话把链接上的节点加到链接数组指定名称name属性，并把链接指向这个节点
            console.log(nodes);
            link.source = nodes[link.source] //link.sourc就是节点值比如Apple
                || (nodes[link.source] = { name: link.source });//(填加节点数据)

            link.target = nodes[link.target] || (nodes[link.target] = { name: link.target });
        });

        var width = 1520,
            height = 600;

        var force = d3.layout.force()
            .nodes(d3.values(nodes))
            .links(links)
            .size([width, height])
            .linkDistance(60)
            .charge(-300)
            .on("tick", tick)
            .start();

        var svg = d3.select("body").append("svg")
            .attr("width", width)
            .attr("height", height);
        //(3)为链接添加线
        var link = svg.selectAll(".link")
            .data(force.links())
            .enter().append("line")
            .attr("class", "link");

        var colors = d3.scale.category20();

        link.style("stroke", function (d) {//  设置线的颜色  
            return colors(d.color);
        })
            .style("stroke-width", function (d, i) {//设置线的宽度  
                return d.weight;
            });
        //(4)为链接添加节点
        var node = svg.selectAll(".node")
            .data(force.nodes())
            .enter().append("g")
            .attr("class", "node")
            .on("mouseover", mouseover)
            .on("mouseout", mouseout)
            .call(force.drag);


        //设置圆点的半径，圆点的度越大weight属性值越大，可以对其做一点数学变换                             
        function radius(d) {
            if (!d.weight) {//节点weight属性没有值初始化为1（一般就是叶子了）
                d.weight = 1;
            }
            return Math.log(d.weight) * 10;
        }
        node.append("circle")
            .attr("r", function (d) {  //设置圆点半径                      
                return radius(d);
            })
            .style("fill", function (d) { //设置圆点的颜色          
                return colors(d.weight * d.weight * d.weight);
            });

        node.append("text")
            .attr("x", 12)
            .attr("dy", ".35em")
            .text(function (d) { return d.name; });

        function tick() {//打点更新坐标
            link
                .attr("x1", function (d) { return d.source.x; })
                .attr("y1", function (d) { return d.source.y; })
                .attr("x2", function (d) { return d.target.x; })
                .attr("y2", function (d) { return d.target.y; });

            node
                .attr("transform", function (d) {
                    return "translate(" + d.x + "," + d.y + ")";
                });
        }

        function mouseover() {
            d3.select(this).select("circle").transition()
                .duration(750)
                .attr("r", function (d) {  //设置圆点半径                      
                    return radius(d) + 10;
                });
        }

        function mouseout() {
            d3.select(this).select("circle").transition()
                .duration(750)
                .attr("r", function (d) {  //恢复圆点半径                      
                    return radius(d);
                });
        }
    </script>

</body>

</html>